Mitsubishi Heavy Industries Marine Structure Co., Ltd. (MHIMST) was established in January 2018, which succeed to construction of large ships in Nagasaki, manufacture and repair of marine structure from Mitsubishi Heavy Industries, Ltd. (MHI)

MHIMST carries on construction of large ships making use of the premises and human resources of the Koyagi Plant of MHI's Nagasaki Shipyard & Machinery Works. And we also expand business in manufacture of marine steel structures.

President & CEOKunio Shiiba

Kunio Shiiba


1. MONOZUKURI from the customers’ point of view
Always willing to listen to our customers to realize reliable “MONOZUKURI.”
2. MONOZUKURI with safety and quality as the first priorities
Always pay attention to safety and quality and stay loyal to the basics to realize consistent “MONOZUKURI.”
3. MONOZUKURI as an opportunity for self-improvement
Always seek to improve the skills and knowledge to realize "MONOZUKURI” that is a cut above the rest.


Company Name Mitsubishi Heavy Industries Marine Structure Co., Ltd.
Head office 180 Koyagi-machi, Nagasaki City, Nagasaki, Japan
President & CEO Kunio Shiiba
Business operations Construction of large ships, manufacture and repair of marine structures
Establishment January 1, 2018
Capital 300 Million Yen (MHI: 100%)


(As of April 1, 2019)



1857 Nagasaki Yotetsusho Foundry was established as Japan’s first warship repair facility. (Origin of Nagasaki Shipyard & Machinery Works)
1870 Tsukumo Shokai began operations.
1884 Shipbuilding operation began.
1886 Company was renamed Mitsubishi Sha.
1887 Mitsubishi Sha purchased Nagasaki Shipyard & Machinery Works.
1893 Mitsubishi Goshi Kaisha was established.
1907 Shipbuilding Division of Mitsubishi Goshi Kaisha was established.
1914 Hikoshima Shipyard of Mitsubishi Goshi Kaisha began operations. (Origin of Shimonoseki Shipyard & Machinery Works)
1917 Mitsubishi Shipbuilding & Engineering Co., Ltd. was established.
1934 Company was renamed Mitsubishi Heavy-Industries, Ltd
1950 West Japan Heavy-Industries, Ltd., Central Japan Heavy-Industries, Ltd. and East Japan Heavy-Industries, Ltd. were established.
1952 The works were renamed Mitsubishi Shipbuilding & Engineering Co., Ltd., Shin Mitsubishi Heavy-Industries, Ltd. and Mitsubishi Nippon Heavy-Industries, Ltd.
1964 The three independent companies of Mitsubishi Heavy Industries, decentralized in 1950, were remerged into a single company named Mitsubishi Heavy Industries, Ltd. (Nagasaki Shipyard & Machinery Works, Kobe Shipyard & Machinery Works, Shimonoseki Shipyard & Machinery Works, Yokohama Shipyard & Machinery Works, Hiroshima Shipyard & Machinery Works)
1972 The Koyagi Building Dry Dock was completed.
The Koyagi Repair Dry Dock was completed in May 1973.
2008 A 1200-ton goliath crane was completed at the Koyagi Building Dry Dock.
2015 Koyagi Works at Nagasaki was spun off to two group companies. Mitsubishi Heavy Industries Shipbuilding Co., Ltd. and Mitsubishi Heavy Industries Hull Production Co., Ltd.
2018 Mitsubishi Shipbuilding Co., Ltd. and Mitsubishi Heavy Industries Marine Structure Co., Ltd. were established.